Riska’s rope has similar stats but is 100 feet long. Other stats apply as per a Rope of Climbing:

A 100 foot long rope of climbing is no thicker than a wand, but is strong enough to support 3,000 pounds. Upon command, the rope snakes forward, upward, downward, or in any other direction at ten feet per round, attaching itself securely wherever its owner desires. It can unfasten itself and return in the same manner.

A rope of climbing can be commanded to knot or unknot itself. This causes large knots to appear at one foot intervals along the rope. Knotting shortens the rope to an 80 foot length until the knots are untied, but lowers the DC of climb checks while using it by 10. A creature must hold one end of the rope when its magic is invoked.